| As the first vehicle to be fired in the city,city main battle fire fighting vehicle is a kind of fire fighting vehicles with comprehensive fire fighting and rescue capability and its cost performance is much higher than ordinary tank fire trucks.However,city main battle fire fighting vehicle has a complicated structure,a long product design cycle,and a slow optimization process,which contradicts the requirements for high-performance product serialization development in the market.Based on the analysis of the traditional design process of city main battle fire fighting vehicle,this paper studied the structural composition of it and divided the functional modules and established a selection database.Combined with secondary development technology,a paramtric design system of city main battle fire fighting vehicle was created to quickly present threedemensional models of city main battle fire fighting vehicle which met customer requirements.Firstly,in this paper,the development of parametric design,top-down design and CAD/CAE integration technology,and the development and applicatgion of domestic and international city main battle fire fighting vehicle are introduced in detail.In view of the shortcomings in the current research,the necessity of implementing parametric design to improve the design efficiency of city main battle fire fighting vehicle is illustrated.The content of the research about the topic are overviewed.Secondly,the optimal module division result of city main battle fire fighting vehicle is obtained by the use of module division method based on product function,combined with genetic algorithm.And through the module reorganization,the structural composition of the city main battle fire fighting vehicle under different functions is obtained.Moreover,the functions and requirements of the parametric design system are analyzed to choose Access,Pro/E,ANSYS and Visual Studio as the supporting softwares and development tools for system development.Thirdly,the dimensional structure parameters and operational performance parameters and constraint relationships of modules are extracted.Based on the topdown design method of multi-skeleton model,parametric 3D models are created in Pro/E through multi-level and multi-functional skeleton modeling.And the aotomatic technology based on coordinate system constraints is used to realize the automatic assembly.Meanwhile,the finite element model of the sub-frame is eatablished in ANSYS,and the static analysis and free modal analysis under bending,torsion,braking and turning conditions are carried out.The results of finite element analysis show that the sub-frame meets the strength and stiffness requirements and does not resonate.Through the analysis process,the analysis method is effective.It can be used as the basis of parametric finite element analysis of the sub-frame and applied to the parametric design system.Finally,combined with MFC,ADO,Pro/Toolkit and APDL,the CAD/CAE integrated system is built.The design and selection are integrated into a unified user platform,in order to realize the multi-function matching and parametric design through mutual switching between different interfaces. |
